1. Field of the Invention
The present invention relates to boards for carrying people over snow, such as snowboards or snow skis, and more particularly pertains to edge structures for such boards, the edge structures provided to prevent a downhill edge from "catching".
2. Description of the Prior Art
The use of boards for carrying people over snow, such as snowboards and snow skis, is well known in the prior art. Although the text of this application is primarily directed to snowboards, it will be readily understood that the principles and structures of the present invention discussed herein are applicable to a variety of boards for traversing snow, such as snowboards and snow skis.
Known prior art snowboard and ski structures include U.S. Pat. Nos. 5,462,304, 5,580,078, 4,974,868, 4,778,710, 4,175,766, 4,951,960 and 3,751,054.
Generally, snowboards have an elongate shaped body with a tip portion, also known as a "nose" or "shovel", a central portion, which may also be referred to as a "waist", and an end portion, also known as a "tail", located, respectively, along a longitudinal axis. The snowboard has a slippery bottom surface, also known as a running surface, for contact with the snow. The running surface has opposite lateral edges substantially parallel with the longitudinal axis of the board. Each edge may have a slight sidecut, thus giving the snowboard a slightly hourglass shaped body when viewed from above. The running surface curves upwardly in at least the forwardmost portion of the nose, and in some board designs, at the rearwardmost portion of the tail. The running surface may also have a slight arch from the tall to the nose along the longitudinal axis. A top surface, also known as the "deck", is provided to support a rider. Bindings on the deck in the central portion of the board secure the rider to the board. The bindings are provided such that the rider stands substantially sideways on the board with his feet skewed somewhat towards the nose of the board.
The basic dimensions of a snowboard are determined by several main factors. The central portion of a snowboard must generally be wide enough to accommodate the substantially perpendicularly positioned feet of a rider, without toes and/or heels extending beyond the edges of the deck to drag in the snow and negatively affect the performance of the snowboard. To facilitate turning and control of the snowboard, the nose and tail are generally slightly wider than the central portion of the board, thus giving the snowboard the hourglass shape. The slightly broader dimension of the nose and tail portions significantly increases the rider's ability to control the direction of travel of the board by facilitating turns.
The above design parameters, in particular, the central portion which is wide enough to accommodate the perpendicularly positioned feet of the rider, and the slightly wider nose and tail to facilitate turning, result in a broad running surface. A broad running surface permits the snowboard to slide quickly over slippery surfaces, such as snow or ice, particularly with the weight of a rider on the deck of the snowboard, and particularly on inclined snow surfaces. When substantial portions of the running surface are in contact with the snow surface, such as, for example, when the running surface is flat on the snow surface, the snowboard tends to slide more quickly, and with less control. Control of a snowboard sliding on snow is accomplished by using the edges of the running surface to stop and turn the snowboard. Turning the snowboard controls the speed and direction of travel of the snowboard. In particular, a skilled snowboard rider controls the speed and direction of travel of the snowboard by "carving" turns in the snow. This is accomplished by the rider shifting his weight on the snowboard such that one lateral edge of the running surface "digs in" to the snow, and, correspondingly, the opposite lateral edge is lifted from the snow, and less of the running surface contacts the snow surface. The lateral edge of the snowboard that "digs in" will hereinafter be referred to as the "carving edge". Generally speaking, the "carving edge" is the lateral edge of the running surface relatively closest to the top of the incline being traversed, also known as the "uphill edge" of the running surface.
A snowboard can be slowed by reducing the running surface in contact with the snow, and/or by traversing across the fall line of a slope rather than down the fall line. The fall line of a slope is the most direct route down the slope. Conversely, the speed of the snowboard can be increased by increasing the running surface in contact with the snow, and/or by traveling along the fall line of the slope. Thus, the speed of the board can be controlled by controlling the amount of running surface in contact with the snow, and by controlling the direction of travel relative to the fall line of the slope. By carving turns with the carving edge of the running surface, a rider can control both his speed and direction by, for example, reducing the apparent steepness of his path of travel on a slope, i.e., by steering the snowboard across the fall line of the slope, or even by steering the snowboard up the slope. Carving turns is therefore critical to the control of the snowboard. The edges of the running surface are in turn critical to carving turns. Other design features of the snowboard, such as the slight arch of the running surface, the flexibility or stiffness of the snowboard, and the slight hourglass shape of the snowboard also contribute to control of the snowboard. A skilled rider on a properly designed snowboard can carve turns to precisely control the speed and direction of travel of the board.
However, for a person first learning to ride a snowboard, i.e., a novice, the concept of carving a turn is a skill that must be learned by practice. Unfortunately for a beginning snowboard rider, the broad running surface of the snowboard, and the tendency of gravity to act on a weight capable of sliding, can quickly cause a novice to careen out of control on even a slight incline. Furthermore, while learning to carve a turn by digging in the carving edge, i.e., the uphill edge, of the running surface, novices frequently lose their balance or otherwise cause the wrong edge of the running surface, i.e., the "downhill edge" or "free edge" (generally the lateral edge of the running surface relatively closer to the bottom of the incline being traversed) to dig in. Digging in the downhill edge of the running surface is known as "catching an edge". Catching an edge may cause the snowboard to stall or stop. The snowboard rider, particularly the novice, tends to lose control of the board and, typically, will fall. Novice riders typically "catch an edge" numerous times before they master the skill of carving a turn with the uphill edge of the running surface. The resulting frequent falls associated with catching an edge can cause a novice great discomfort in the form of pain due to injuries and exhaustion due to the effort required to recover from the falls. Furthermore, serious injury can result from the falls.
Thus, the most important skill in snowboarding, i.e., carving a turn, is also one of the most difficult skills to master due to the tendency of the novice snowboard rider to catch an edge and fall.
U.S. Pat. No. 5,462,304 to Nyman addresses the problem of catching an edge by permanently modifying both lateral edges of the running surface such that each lateral edge has a first inward facing edge, and a second elevated outward facing edge. A downwardly and outwardly directed sloping side surface angles upward from the first edge to the second edge, connecting the two edges. The second elevated outward facing edge is positioned with sufficient height relative to the running surface that the outward facing edge does not "catch". The downwardly and outwardly directed sloping surface connecting the first inward facing edge and the second outward facing edge is sufficiently angled that it also does not "catch". However, the board as disclosed and claimed by Nyman has several drawbacks. The permanent and rather radical modifications to both edges of the snowboard as taught by Nyman would be difficult to maintain due to the complex cross-sectional shape of each edge. Furthermore, the edges as taught by Nyman occupy portions of the running surface of the snowboard that are flat on a conventional snowboard. Thus, compared to a conventional snowboard, the edges as taught by Nyman reduce the width of the flat portion of the running surface, i.e., the surface that provides speed to the snowboard, thus slowing the board. Furthermore, the edges as taught by Nyman eliminate the ability of the board to slide laterally when such a slide is desired, thus reducing the maneuverability of such a board. In addition, since "catching an edge" is typically only a major problem for novice snowboard riders, as a rider's skills increase, the rider will rapidly outgrow a board made according to the teaching of Nyman. Most importantly, since Nyman teaches permanently modifying the carving edge and the free edge of a snowboard, it may not be possible for a novice rider learning to carve turns on a snowboard with the edges modified according to Nyman to learn how to carve a turn on a snowboard having conventional style running surface edges. A novice rider learning on a snowboard with a carving edge modified according to the teachings of Nyman would only learn to carve turns on edges modified according to Nyman and, therefore, may not be suitably skilled to make a transition to a snowboard having a conventional edge.
U.S. Pat. No. 5,644,808 to Whidden et al. is directed to an edge covering for a ski or snowboard. The edge covering is an elongated cylindrical channel which frictionally engages the edge of a ski or snowboard. The disclosure of Whidden et al. teaches that the edge covering is for protecting the edges of the ski or snowboard from unintentional engagement with surrounding objects. The specification does not teach or suggest that the edge covering can be in place on the ski or snowboard when the ski or snowboard is actively being used by a rider. As depicted in the drawings, the edge covering is applied to both lateral edges, and to the tip of the ski or snowboard. According to the specification, the edge of the tail may also be covered. As shown in the drawings, the edge covering taught by Whidden et al. would render the ski or snowboard useless for riding purposes because the edge covering provided on both lateral edges would prevent the user from carving turns. An attempt to use the ski or snowboard with the edge cover as taught by Whidden et al. in place would, due to the users inability to carve a turn, likely result in injury to the user.
In view of the foregoing disadvantages, there is a need for novices learning to ride a snowboard, for a snowboard modified to facilitate control and stability of the snowboard by preventing the stalls and falls caused by a downhill edge catching.